<?php
	/*
		----------------------------------------------------------------
		Easy Reflections by Richard Davey, Core PHP (rich@corephp.co.uk)
		v2 - 2nd March 2007
        v2.1 - 5th January 2008
        Updates include changes by Monte Ohrt (monte@ohrt.com)
		----------------------------------------------------------------
		You are free to use this in any product, or on any web site.
		Latest builds at: http://reflection.corephp.co.uk
		----------------------------------------------------------------
		
		This script accepts the following $_GET parameters:
		
		img		        required	The source image (to reflect)
		height	        optional	Height of the reflection (% or pixel value)
		bgc		        optional	Background colour to fade into, default = #ffffff
        fade_start      optional    Start the alpha fade from whch value? (% value)
        fade_end        optional    End the alpha fade from whch value? (% value)
		jpeg	        optional	Output will be JPEG at 'param' quality (default 80)
        cache           optional    Save reflection image to the cache? (boolean)
        merge           optional    Output image contains both source and reflection? (boolean, default false)
	*/
    
    //  Image Flow users - If you wuold like to hard-code the background colour into this script, do so here by
    //  uncommenting the following line and changing the colour value to whatever you need:

    //  $bgc = 'ffffff';
	
	//	PHP Version sanity check
	if (version_compare('4.3.2', phpversion()) == 1)
	{
		echo 'This version of PHP is not fully supported. You need 4.3.2 or above.';
		exit();
	}
	
	//	GD check
	if (extension_loaded('gd') == false && !dl('gd.so'))
	{
		echo 'You are missing the GD extension for PHP, sorry but I cannot continue.';
		exit();
	}
	
	//	Our allowed query string parameters

    //  To cache or not to cache? that is the question
    if (isset($_GET['cache']))
    {
        if ((int) $_GET['cache'] == 1)
        {
            $cache = true;
        }
        else
        {
            $cache = false;
        }
    }
    else
    {
        $cache = false;
    }

	//	img (the image to reflect)
	if (isset($_GET['img']))
	{
		$source_image = $_GET['img'];
		$source_image = str_replace('://','',$source_image);
		$source_image = $_SERVER['DOCUMENT_ROOT'] . DIRECTORY_SEPARATOR . $source_image;
        
        if (file_exists($source_image))
        {
            if ($cache)
            {
                $cache_dir = dirname($source_image);
                $cache_base = basename($source_image);
                $cache_file = 'refl_' . md5($_SERVER['REQUEST_URI']) . '_' . $cache_base;
                $cache_path = $cache_dir . DIRECTORY_SEPARATOR . $cache_file;

                if (file_exists($cache_path) && filemtime($cache_path) >= filemtime($source_image))
                {
                    // Use cached image
                    $image_info = getimagesize($cache_path);
                    header("Content-type: " . $image_info['mime']);
                    readfile($cache_path);
                    exit();
                }
            }
        }
        else
        {
          echo 'Cannot find or read source image';
          exit();
        }
	}
	else
	{
		echo 'No source image to reflect supplied';
		exit();
	}

	//	bgc (the background colour used, defaults to white if not given)
	if (isset($_GET['bgc']) == false && isset($bgc) == false)
	{
		$red = 255;
		$green = 255;
		$blue = 255;
	}
	else
	{
        //    Extract the hex colour
        if (isset($bgc))
        {
            $hex_bgc = $bgc;
        }
        else
        {
            $hex_bgc = $_GET['bgc'];
        }
		
		//	Does it start with a hash? If so then strip it
		$hex_bgc = str_replace('#', '', $hex_bgc);
		
		switch (strlen($hex_bgc))
		{
			case 6:
				$red = hexdec(substr($hex_bgc, 0, 2));
				$green = hexdec(substr($hex_bgc, 2, 2));
				$blue = hexdec(substr($hex_bgc, 4, 2));
				break;
				
			case 3:
				$red = substr($hex_bgc, 0, 1);
				$green = substr($hex_bgc, 1, 1);
				$blue = substr($hex_bgc, 2, 1);
				$red = hexdec($red . $red);
				$green = hexdec($green . $green);
				$blue = hexdec($blue . $blue);
				break;
				
			default:
				//	Wrong values passed, default to white
				$red = 255;
				$green = 255;
				$blue = 255;
		}
	}
	
	//	height (how tall should the reflection be?)
	if (isset($_GET['height']))
	{
		$output_height = $_GET['height'];
		
		//	Have they given us a percentage?
		if (substr($output_height, -1) == '%')
		{
			//	Yes, remove the % sign
			$output_height = (int) substr($output_height, 0, -1);

			//	Gotta love auto type casting ;)
			if ($output_height < 10)
			{
				$output_height = "0.0$output_height";
			}
			else
			{
				$output_height = "0.$output_height";
			}
		}
		else
		{
			$output_height = (int) $output_height;
		}
	}
	else
	{
		//	No height was given, so default to 50% of the source images height
		$output_height = 0.50;
	}
	
	if (isset($_GET['fade_start']))
	{
		if (strpos($_GET['fade_start'], '%') !== false)
		{
			$alpha_start = str_replace('%', '', $_GET['fade_start']);
			$alpha_start = (int) (127 * $alpha_start / 100);
		}
		else
		{
			$alpha_start = (int) $_GET['fade_start'];
		
			if ($alpha_start < 1 || $alpha_start > 127)
			{
				$alpha_start = 80;
			}
		}
	}
	else
	{
		$alpha_start = 80;
	}

	if (isset($_GET['fade_end']))
	{
		if (strpos($_GET['fade_end'], '%') !== false)
		{
			$alpha_end = str_replace('%', '', $_GET['fade_end']);
			$alpha_end = (int) (127 * $alpha_end / 100);
		}
		else
		{
			$alpha_end = (int) $_GET['fade_end'];
		
			if ($alpha_end < 1 || $alpha_end > 0)
			{
				$alpha_end = 0;
			}
		}
	}
	else
	{
		$alpha_end = 0;
	}

	/*
		----------------------------------------------------------------
		Ok, let's do it ...
		----------------------------------------------------------------
	*/
	
	//	How big is the image?
	$image_details = getimagesize($source_image);
	
	if ($image_details === false)
	{
		echo 'Not a valid image supplied, or this script does not have permissions to access it.';
		exit();
	}
	else
	{
		$width = $image_details[0];
		$height = $image_details[1];
		$type = $image_details[2];
		$mime = $image_details['mime'];
	}
	
	//	Calculate the height of the output image
	if ($output_height < 1)
	{
		//	The output height is a percentage
		$new_height = $height * $output_height;
	}
	else
	{
		//	The output height is a fixed pixel value
		$new_height = $output_height;
	}

	//	Detect the source image format - only GIF, JPEG and PNG are supported. If you need more, extend this yourself.
	switch ($type)
	{
		case 1:
			//	GIF
			$source = imagecreatefromgif($source_image);
			break;
			
		case 2:
			//	JPG
			$source = imagecreatefromjpeg($source_image);
			break;
			
		case 3:
			//	PNG
			$source = imagecreatefrompng($source_image);
			break;
			
		default:
			echo 'Unsupported image file format.';
			exit();
	}
	
	/*
		----------------------------------------------------------------
		Build the reflection image
		----------------------------------------------------------------
	*/

	//	We'll store the final reflection in $output. $buffer is for internal use.
	$output = imagecreatetruecolor($width, $new_height);
	$buffer = imagecreatetruecolor($width, $new_height);

	//	Copy the bottom-most part of the source image into the output
	imagecopy($output, $source, 0, 0, 0, $height - $new_height, $width, $new_height);
	
	//	Rotate and flip it (strip flip method)
    for ($y = 0; $y < $new_height; $y++)
    {
       imagecopy($buffer, $output, 0, $y, 0, $new_height - $y - 1, $width, 1);
    }

	$output = $buffer;
	
	/*
		----------------------------------------------------------------
		Apply the fade effect
		----------------------------------------------------------------
	*/
	
	//	This is quite simple really. There are 127 available levels of alpha, so we just
	//	step-through the reflected image, drawing a box over the top, with a set alpha level.
	//	The end result? A cool fade into the background colour given.

	//	There are a maximum of 127 alpha fade steps we can use, so work out the alpha step rate

	$alpha_length = abs($alpha_start - $alpha_end);

	for ($y = 0; $y <= $new_height; $y++)
	{
		//  Get % of reflection height
		$pct = $y / $new_height;

		//  Get % of alpha
		if ($alpha_start > $alpha_end)
        {
            $alpha = (int) ($alpha_start - ($pct * $alpha_length));
        }
        else
        {
            $alpha = (int) ($alpha_start + ($pct * $alpha_length));
        }

		imagefilledrectangle($output, 0, $y, $width, $y, imagecolorallocatealpha($output, $red, $green, $blue, $alpha));
		
	}

    /*
        ----------------------------------------------------------------
        Source Image Merge required?
        ----------------------------------------------------------------
    */
    
    if (isset($_GET['merge']) && $_GET['merge'] == true)
    {
        $merged_output = imagecreatetruecolor($width, $new_height + $height);

        //  Copy the source image
        imagecopy($merged_output, $source, 0, 0, 0, 0, $width, $height);
        
        //  Copy our new reflection
        imagecopy($merged_output, $output, 0, $height, 0, 0, $width, imagesy($output));
        
        //  Replace the output with this new version
        $output = $merged_output;
    }

	/*
		----------------------------------------------------------------
		Output our final PNG / JPEG
		----------------------------------------------------------------
	*/

	if (headers_sent())
	{
		echo 'Headers already sent, I cannot display an image now. Have you got an extra line-feed in this file somewhere?';
		exit();
	}
	else
	{
		//	If you'd rather output a JPEG instead of a PNG then pass the parameter 'jpeg' (no value needed) on the querystring

		if (isset($_GET['jpeg']))
		{
			$quality = (int) $_GET['jpeg'];
			
			if ($quality < 1 || $quality > 100)
			{
				$quality = 80;
			}
			
			//	JPEG (the final parameter = the quality, 0 = terrible, 100 = pixel perfect)
			header("Content-type: image/jpeg");
			imagejpeg($output, '', $quality);
			
            // Save cached file
            if ($cache)
            {
                imagejpeg($output, $cache_path, $quality);
            }
			
		}
		else
		{
			//	PNG
			header("Content-type: image/png");
			imagepng($output);

            // Save cached file
            if ($cache)
            {
                imagepng($output, $cache_path);
            }
		}

		imagedestroy($output);
		exit();
	}
?>